1. Field of the Invention
The present invention relates to an electronic component, an electronic device, and a manufacturing method for the electronic component, and more particularly, to an electrochemical cell such as an electric double-layer capacitor.
2. Description of the Related Art
The electric double-layer capacitor is a device which is charged through polarization of ions in an electrolyte and discharged, thereby supplying electric power.
The electric double-layer capacitor is characterized by this charging/discharging function, and hence is used, for example, in backup power sources for a clock function and a semiconductor memory for electronic devices, or used in standby power sources for electronic devices such as microcomputers and IC memories.
In particular, the electric double-layer capacitor capable of surface mounting can be downsized and reduced in thickness, and hence is suitable for thin mobile terminals.
In order to meet such demands for downsizing and reduction in thickness, the following Japanese Patent Application Laid-open No. 2001-216952 proposes, as described below, an electric double-layer capacitor in which a polarizable electrode and an electrolyte are accommodated in a container including a recessed portion and an opening portion is sealed with a sealing plate.
FIG. 10 is a cross-sectional view of a conventional electric double-layer capacitor 100.
On a bottom surface of a recessed container 102, which has a recessed portion 150 formed therein and is made of a ceramics, a metallic layer 111 is provided. A positive electrode 106 is bonded onto an upper surface of the metallic layer 111. The metallic layer 111 passes through the recessed container 102 to be electrically connected to a positive terminal 112 on a rear surface of the recessed container 102. In this manner, the positive electrode 106 is electrically connected to the positive terminal 112 via the metallic layer 111.
Further, a sealing plate 103 made of a metal is bonded onto an opening portion of the recessed portion 150 by a bonding material 108 made of a metal, to thereby seal the recessed portion 150. On a side surface of the recessed container 102, there is formed a metallic layer 109 connecting the bonding material 108 and a negative terminal 110 formed on the rear surface of the recessed container 102. A negative electrode 105 is bonded onto a lower surface of the sealing plate 103, and is electrically connected to the negative terminal 110 via the sealing plate 103, the bonding material 108, and the metallic layer 109.
Between the negative electrode 105 and the positive electrode 106, there is provided a separator 107 for preventing the negative electrode 105 and the positive electrode 106 from short-circuiting, and further, an electrolyte is sealingly filled in the recessed portion 150.
Further, the electric double-layer capacitor 100 stores charges when a voltage is applied to the negative terminal 110 and the positive terminal 112, and releases the stored charges to supply power for maintaining a clock function, to supply power to a memory, and to supply power for other purposes.
However, when strong electrical connection is desired between the sealing plate 103 and the negative electrode 105, it has been necessary to adhere the electrode onto the sealing plate 103 by a conductive adhesive in advance.
Therefore, after preparing two kinds of parts, that is, the recessed container 102 onto which the positive electrode 106 is adhered and the sealing plate 103 onto which the negative electrode 105 is adhered, the assembly is performed. Therefore, steps at the time of manufacture are complicated, which causes reduction in yield.